I have been a Civil War buff since childhood, so I confess a life long interest. And I do meet many men who wish their wives shared theirs. I have 2 suggestions.

1) Quote to your spouse or girlfriend the Jay Leno situation: "Some guys have many wives or girlfriends. I've been married for 27 years to the same woman, but have a gazillion cars." In other words, I believe the moral of the story is that a strong interest in a subject or hobby helps keep spouses happy in their marriages. And as a friend of mine said: "The more interests I acquire, the happier I am." You can only be happy for yourself, by yourself. I have found that happines is meaningful accomplishments and sharing. It's a good rule of thumb for raising kids too. I would also think that if you relate why the CW is meaningful to you, your wives will respect that and support you in it. Sometimes it's really important to verbalize things.

2) Most histories of the Civil War are not written in a way that will interest women. Men want to write the "great war treatise or novel." Women are relational people. They want to read about how things or people relate. I think that's why I hated math but loved computers that relate things. Guys love cars, girls love horses that they can relate to. One of the reasons I wrote my work of fiction South Under a Prairie Sky: The Journal of Nell Churchill, US Army Nurse & Scout, was to write a book that women could relate to, although men like it, too. You can also look at my webpage: "Springing to the Call: A Documentary View of Women in the American Civil War" at http://www.nymas.org -- right sidebar, scroll down. Find a Civil War woman who you think your wife will like and see if you can interest her in her. The CW women are really great and many of their stories and letters are better than the men's. Or research the wives of your favorite generals: Libby Custer, Mrs. S/w Jackson, Mrs. Gen. Barlow, Princess Salm Salm, Nadine Turchin, Mary Bickerdyke, Mrs. Malinda Blalock are all wonderful women. I also highly recommend: http://www.civilwarwomen.blogspot.com which has about 100 CW inspiring biographies, as well as the letters of nurses Katherine Wormeley and Cornelia Hancock, still in print. Or buy and share a dog of the kind that a favorite regiment had, or a bird! The mascot stories are great, too. But I wouldn't recommend a bear, like the Minnesota guys had.